Commands by matthewdavis (3)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Stream system sounds over rtmp
sox (SOund eXchange) can capture the system audio be it a browser playing youtube or from hardware mic and can pipe it to ffmpeg which encodes it into flv and send it over rtmp. Tested using Red5 rtmp server.

Find the package that installed a command

Test for Weak SSL Ciphers
...if you get a certificate back, the server is accepting weak SSL ciphers

List files older than one year, exluding those in the .snapshot directory
Useful when you want to cron a daily deletion task in order to keep files not older than one year. The command excludes .snapshot directory to prevent backup deletion. One can append -delete to this command to delete the files : $ find /path/to/directory -not \( -name .snapshot -prune \) -type f -mtime +365 -delete

find and reduce 8x parallel the size of PNG images without loosing quality via optipng

Listen YouTube radios streaming
Listen YouTube radios streaming. I use it on an alias to easily enter kinda flow state for study/programming.

Show network throughput
Real gurus don't need fancy tools like iftop or jnettop.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

copy paste multiple binary files
Useful when you have multiple files or binary files that you need to transfer to a different host and scp or the like is unavailable. To unpack on the destination host copy paste output using the opposite order: openssl enc -d -base64 | gunzip | tar -x Terminate openssl input using ^d Note: gzip is outside of tar because using -z in tar produces lots of extra padding.

Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

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